1. Field of the Invention
The present invention relates to a process for the preparation of a toner polymer, and more particularly to a preparation process for a toner polymer which is excellent in moisture resistance, can maintain constant electrostatic friction over a long period and has a long service life.
2. Description of the Prior Art
Many inventions on the preparation of polymers for dry toners have been conventionally conducted. The preparation processes include suspension polymerization, bulk polymerization, desolvation after solution polymerization and salting-out after emulsion polymerization. Suspension polymerization is the most excellent process in economy.
In conventional suspension polymerization using a dispersant, the dispersant remains to a certain degree by anchoring on the surface of polymer particles, even though washing it thoroughly carried out after polymerization. When a toner is prepared by using these polymer particles as a raw material, the remaining dispersant causes an adverse effect on such toner properties as moisture resistance, stability of electrostatic charge and fixing ability. Hence the dispersant leads to problems in the deterioration of image quality in the case that the toner is used at increased temperatures or high humidity and the number of duplications cycles is increased.
This tendency can be somewhat overcome by using a nonionic dispersant in place of an anionic or cationic dispersant used in suspension polymerization. Improvements to date, however, have been unsatisfactory.